diff --git a/src/jdwp/jdwp_priv.h b/src/jdwp/jdwp_priv.h
index 7a6a528..98ae3b9 100644
--- a/src/jdwp/jdwp_priv.h
+++ b/src/jdwp/jdwp_priv.h
@@ -32,6 +32,9 @@
 #define kJDWPHeaderLen  11
 #define kJDWPFlagReply  0x80
 
+#define kMagicHandshake     "JDWP-Handshake"
+#define kMagicHandshakeLen  (sizeof(kMagicHandshake)-1)
+
 /* DDM support */
 #define kJDWPDdmCmdSet  199     /* 0xc7, or 'G'+128 */
 #define kJDWPDdmCmd     1